1. Field
This invention broadly concerns a uniquely constructed fuel ignition device and method for initiating combustion of fuel (carburetor or fuel injection) in the combustion chamber of internal combustion engines.
Detonation in the combustion chamber of an internal combustion engine is very destructive in that it causes significant damage such as breaking piston rings, burning holes in pistons, and destroying piston ring lands. The present invention will essentially eliminate detonation in the combustion chamber of an internal combustion engine.
Detonation occurs in conventional engines when an appreciable portion of the fuel/air charge ignites due to spontaneous combustion. This spontaneous combustion results from the last portion of the last fraction of the fuel-air charge in the combustion chamber being subjected to high pressure and temperature. As the spark plug ignites the fuel-air mixture in the combustion chamber a flame/pressure front is created. This flame/pressure front burns across the combustion chamber. As the flame front expands it causes an increase in pressure in areas outside of the flame front which compresses the remaining fuel-air mixture. This compression causes an increase in temperature high enough to bring about decomposition of fuel remaining in the areas outside the flame front. The fuel breaks into lower molecular weight compounds which have much lower auto ignition temperatures than the original fuel. As compression increases, a corresponding increase in temperature occurs which causes these lower molecular weight compounds to auto-ignite/detonate in front of the flame front. Auto-ignition/detonation of un-decomposed fuel ahead of the flame front can also occur if the pressure/temperature increase in front of the flame front is great enough and the time lag is long enough. This Detonation occurs in areas not yet ignited by the flame front caused by spark plug ignition.
2. Prior Art
Typical prior art devices which employ what is termed a “pre-combustion” chamber, is disclosed in U.S. Pat. No. 5,924,402 wherein the transfer passages 52 are designed to be angled symmetrically about an axis “A”. This structure and angle are obviously not intended to be able to direct any of the ejected flame in a generally horizontal direction or otherwise variable direction and, it would appear, could lead to burning of the piston tops of conventional engines.
The time lag between spark plug ignition and auto-ignition (detonation) depends upon the flame front speed. In accordance with the present invention, it has been discovered that if the flame ejection speed from the ejector nozzle were high enough, and if the flame front were directed towards fuel concentrations, typically the greatest fuel-air volume areas, within the head combustion chamber, the flame front would reach the fuel in the auto-ignition areas before detonation could occur. The device described in detail below will essentially eliminate the detonation by igniting significantly more of the fuel air mixture over a larger initial area by flame ejection speed and directioning, which will reduce the time required for the flame front to travel through the whole fuel air charge in the combustion chamber.
The present device consists of an ignition source such as a conventional spark plug, a fuel air cavity, acceleration tube, and ejection nozzles or ports. On the compression stroke of the piston the following events occur:                1. the fuel air mixture is compressed through the ejection nozzle of the device and upward in the acceleration tube into the fuel air cavity;        2. a timed spark then ignites the fuel in the cavity;        3. the temperature and pressure start to build in the cavity;        4. the flame accelerates down the acceleration tube igniting more fuel as it goes;        5. by the time the flame exits the nozzle it is traveling much faster than what the flame speed would have been if ignited by a conventionally positioned spark plug in the combustion chamber;        6. in addition the fuel is ignited at multiple points depending on the number of ejection nozzles;        7. because the flame exiting the nozzle is under high pressure and is travelling faster than the flame front in the lower pressure combustion chamber, the flame from the nozzle penetrates into the combustion chamber; and        8. the fuel air mixture in the combustion chamber is ignited from numerous locations from the flames ejected from the multiple nozzles which are designedly directionally oriented toward fuel concentrations.        
The time lag from ignition in the fuel/air cavity to the flame front reaching all the way across the combustion chamber is greatly reduced as compared to the time lag experienced with a single source ignition like a spark plug in a conventional combustion chamber.